1. Field
The following description relates to an apparatus and method for transmitting data, and more particularly, to an apparatus for forwarding received data to a data receiving device and a data forwarding method.
2. Description of Related Art
Active studies are being made to provide various multimedia services including voice services in a radio communication environment, and support high speed and high quality data transmission. As one of the candidates, a technique in a multiple-input multiple-output (MIMO) communication system using a channel of a spatial domain has been developed.
A MIMO technique may utilize multiple antennas to increase a channel capacity in an environment with limited frequency resources, to thereby provide a relatively high data rate. The MIMO technique may utilize multiple transmitting/receiving antennas in a channel environment with a large number of scatters, and thus, in theory, may provide a channel capacity in proportion to a number of antennas of one of the transmitting/receiving antennas having a smaller number of antennas.
Also, a technique using a relay has been suggested to increase coverage of a specific base station. Mobile stations may be connected with a relay, and the relay may transmit, to the base station, data received from the mobile station.
However, where the relay is included in a communication system, radio resources such as a time duration for the relay and the like may be needed. For example, assuming that the relay between the base station and the mobile station is operated, the base station may transmit, to the relay, an A message during a T1 time section of downlink time sections, and also transmit, to the mobile station, a B message during a T2 time section of uplink time sections. In this case, the relay may transmit, to the mobile station, the A message during a T3 time section of the downlink time sections, and also transmit, to the base station, the B message during a T4 time section of the uplink time sections.
As described above, so that the A message transmitted from the base station is transmitted to the mobile station via the relay, and the B message transmitted from the mobile station is transmitted to the base station via the relay, a minimum of four time sections such as T1, T2, T3, and T4 may be needed. Where the base station and the mobile station directly transmit/receive the A and B messages without using the relay, only two time sections may be needed. Accordingly, where a relay is further included in a communication system, radio resources such as the time section and the like may be further consumed and the data rate may be reduced.